Spec Mammalia: Eutheria
INTRODUCTION Eutheria, mammals that carry their young in the womb until fully developed, are the most familiar of the mammalian groups - a fact that is not surprising, since this is the group to which humans belong. Spec's eutherians are much less diverse than those of our home timeline, although even in Spec, the "true beasts" make up more than two thirds of the planet's mammalian species. Some eutherians, such as the xenarthrans and primates, are present in both Spec and RL, while others, such as the paraselenodonts, are endemic to this timeline. MAJOR TAXA CIMOLESTA (Beerats, false-colugos, and volegs) XENARTHRA (Armadillos, bullids, and pangolins) Xenarthrans (also called endentates) are a strange group of mammals that split off the main eutherian line quite early in their evolution. Indeed, in RL, Xenarthra and Pholidota, with their oddly-articulated vertebrae and teeth, form sister taxa to all the rest of Eutheria. TAENIODONTIA Taeniodonts are another group of Specworld animals that bear a misleading resemblance to familiar Home-Earth fauna. A casual observer would probably place the lumbering diga-dumdum as a woodchuck or badger or the smaller scuttlebutt as a mole. However, these heavily-built, deep-faced mammals are only very distantly related to the rest of Eutheria. These creatures evolved in North America very early in the Cenozoic. Paleocene fossils show taeniodonts as the middling-sized, plodding enigmas of RL's own prehistory. As in our home timeline, it seems the ecological destruction wrought during the transition from Cretaceous to Tertiary opened up a number of niches into which mammals could radiate. Unlike their counterparts in the familiar history of Home-Earth, however, Spec's taeniodonts failed to go extinct at the end of the Eocene, and continued to thrive through the Cenozoic as an assemblage of borrowers of various sizes. By the Eocene, taeniodonts were already in Asia and possibly Africa, where they swept aside a number of early rodent-like lineages, only later to be pushed into the background (at least in some niches) by the xenotheridians. The Great American Interchange of the Miocene brought taeniodonts into contact with the burrowing xenarthrans, but there seems to have been little conflict involved in this particular mix. Taeniodonts are almost exclusively herbivorous, while the xenarthran bullettes and armadillos are generally insectivorous, so the two clades have managed to coexist peacefully. Taeniodonts are separated from all other placental mammals by several distinctive anatomical features, most notable of which are their molar teeth. These teeth possess very deep roots, and grow constantly throughout the life of the animal, enabling it to tackle a range of abrasive foliage. Taeniodonts, then, do not nibble or gnaw like xenotheridians, but chew their food rather like Home-Earth pandas, using blunt-clawed fingers to shove food into the mouth. As mammals go, taeniodonts are not particularly intelligent, but most species are relatively good-natured. TINGAMARROIDAE In RL, the home timeline, biologists regard the "ungulates" (hoofed mammals) as a single, if highly diverse and varied clade. In Spec, however, Ungulata is undoubtedly paraphyletic, encompassing many non-related clades on the basis of superficial appearance. Throughout Spec's Tertiary, a number of mammalian groups have independently evolved ungulate-like features (namely hooves). Perhaps the best example of this bizarre trend are the tingamarroids, a group of Australian eutherians whose existence patently impossible. Besides the flying p-chiropterans, Tingamarroida forms the only group of placental mammals in the Australian realm. Perhaps tingamarroids migrated from South America before Gondwana had entirely split apart, or perhaps they are descended from some African or Asian species that somehow rafted or swam to Australia. The tingamarroid fossil record nonexistent, and their peculiar anatomy sheds no light on their origins. The tingamarroids (one family, one genus, two species) occupy Tasmania and southern Australia, where they eat grasses and other small vegetation. They are very fleet-footed and skittish, with excellent senses and a nocturnal disposition. Tingamarroids possess cloven hooves like those of the artiodactyls of Home-Earth, but this trait is almost certainly convergent. They are obviously eutherian, bringing offspring to full term in the placenta (womb) and then suckling the newborns for between six and eight months. The teeth of a tingamarroid are quite strange, with large, flattened incisors, totally absent canines, and a set of deep-rooted, ever-growing molars most similar to those of the extinct, RL taeniodonts. Australia, traditionally a land of strange creatures, has surpassed itself with the unassuming tingamarroids. Australia is a land of many strange creatures, but none are as shrouded in mystery as the unassuming tingamarr. The striped tingamarr (Tingamaroida nyahnya) is small, at less than a meter in length, and is the only non-chiropteran eutherian in Australia, making their very existence a puzzle, indeed. Crepuscular herbivores, tingamarrs graze upon grasses and low-growing foliage during the dawn and dusk, when predatory dinosaurs' eyes are less sensitive than the mammals' senses of smell and hearing. Unlike the solitary Tazmanian tingamarr, striped tingamarrs travel in herds of about six individuals, sleeping in abandoned tortoise burrows, thickets, and anywhere else that offers suitable protection. AFROTHERIA Afrotheria is a diverse group of mammals that evolved in Africa from primitive, shrew-like ansestors long ago, when Africa split away from the main Gondwanan body. TENRECIDAE (Tenrecs) MEGAFROTHERIDAE This possibly paraphyletic clade is composed of only two species, the marso and the sut. Both are unusually large (for specworld afrotherers) and possess hoof-like nails and broadly similar dentition. Since both members of this group are known only from dead specimens that have yet to be fully studied, little more can be said about the megafrotheres at this time. If you manage to catch a glimpse of a marso in the forest floor, at first you might think you've seen a large rodent. Though the similarity does exsist, true rodents simply don't exist on Spec, so the animal must be something else, maybe a xenotheridan or a paraselenodont, a metatherian even. Yet each of these guesses would be wrong, as the marso is, in fact, one of Spec's few afrotherians that weigh over a kilogram. It is not easy to think of this 4-6 kg critter as a member of a clade that, in our home timeline, includes elephants, but its resemblance with Arel hyraxes is actually quite obvious even for the layman (hence its latin name, Pseudohyrax). The resemblance is mostly due to convergent evolution, as the common ancestor of the hyrax and marso must have been a rather generic-looking shrew-like mammal. Both hyraxes and marsos share a similiar body size and a herbivorous diet, as well as many internal similarities, most apparent in the skeleton. Differences between a marso and one of RL's true hyraxes are obviously there as well. Unlike the hyrax, marso is not much of a climber, but is more strictly cursorial. (As a rough generalization, all specworld's Afrotheria seem to be swifter and more lightly built than RL afrotheres. This may be partly due to different niches, dinosaurian predation and smaller body sizes.) Marsos are also, to the headache of specmammalologists, very timid animals that shun anything that is bipedal or smells different from what they've encountered before. We have been able to ascertain, however, that marsos are social and are most often found near rivers or other bodies of water. They are, in fact, quite capable swimmers and often flee their terrestrial pursuers via the water. Due mostly to its timid nature, the marso has been, if possible, even harder a beast to capture than its distant relative, the sut. Marsos have been sighted several times since the first Congo expedition, and based on their external appearance, they were at first tentatively classified as xenotheridans. Even today, the species is known mostly from two dead individuals: the holotype and a paratype gunned down by the recent Choo expedition. Living marsos have evaded their would-be captors to this day. What lives in the deep jungles of Congo, looks like a crossbreed of dog and tapir and laughs like hammy hollywood villain? This is a question that kept specbiologist baffled until the first specimen of the elusive sut (Setech occultus) was finally captured. For a years it remained one of the most sought-after spec-cryptids. The creature's very existence has been hotly debated for quite some time, but fortunately not by the spexplorers who finally trapped the beast and brought its secrets to the light. Based on photographic material and eyewitness reports, the sut was at first classified as an aberrant paraselenodont, but the truth turned out to be something much more interesting. A preliminary examination of the captive sut's anatomy revealed characters that hinted of something unlike the already familiar specmammalian clades - yet reminiscent of certain Arel mammals. However, it was only genetic analysis that provided the final proof: the sut was clearly an afrothere. In RL, Afrotheria includes such unlikely relatives as elephant shrews, tenrecs, hyraxes, sirenians, aardvarks and elephants, but in Spec, only the first two groups were thought to have evolved. At least, this was the consensus before the discovery of the sut (and the later discovery of the distantly related marso). Next to those of RL, Spec's Afrotheria is still rather anemic-looking by comparison, it seems the existence of the giant dinosaurs has forced these mammals to remain comparatively small, the 10 kg sut being their largest representative. Besides its taxonomic status, very little definite information known of the sut. Morphologically, it has some similarities with paenungulates, though not enough to erect a specworld version of that clade. Suts have well-developed senses of smell and hearing, and also rather large brains as Spec mammals go. They also possess short, mobile trunks, enlarged claws and pig-like dentition, which all hint that these animals are omnivores, digging for roots, tubers and small animals in the forest floor. Their closest RL equivalents may, therefore, be coatis. There are still many questions about the sut that remain unanswered. What, for instance, is the function of their long tail, how social are they, what purpose do their distinctive vocalizations serve, and why are they restricted to the jungles of middle Africa? It has been speculated that the legendary cackling of the sut (described as a raspy "Eaarh-raah-raah-raah") may be something somewhat akin to the croaking of frogs, or chirping of crickets - attracting the separately living females to the males. This can however not be verified until we know more of the social life of these cryptic animals. Note: The name of the sut comes from the Egyptian god Seth (also known as Set, Sut, Setekh, Setesh and Seteh). This god was often represented by a strange long-snouted animal, which may have been an amalgam of an aardvark and a jackal. This mythical beast inspired the discoverers of the sut to name it after the incarnation of this god - quite appropriately considering that both aardvarks and suts are afrotheres. Originally, the sut was named "seteh", Seteh occultus/proprius(nomen vanum), but the name was then changed with the formal description of the animal to avoid any nomenclatural problems. (The deinonychosaurian genus Seteh was also eventually abandoned, so one could argue that the change was unnecessary, though probably for the better.) CHIROPTERA (Bats) Perhaps most the most notable difference between the familiar bats of RL and those of Spec is absence of the vesper bats (Vespertilionidae) in the latter timeline. Vespertilionidae is the most speciose group of bats, and the second-most speciose group of mammals in the fauna of RL, but on the Specworld they seem never to have evolved. In addition, Molossidae (free-tailed bats and kin) seems to also be absent from Spec. Spec has its fair share of small insectivorous bat species, but here they are mostly represented by emballonurids (sac-winged bats, sheath-tailed bats, and ghost bats). Emballonuridae is an old lineage, stretching back at least to the mid Eocene, and probably further. They are widespred in RL, but the family only includes about 50 species. Here in spec, there are at least 300 species of these small, agile bats and, given their cryptic color and small size, it is likely that twice this many acutally exists in the world of spec. These bats can change the size and shape of their tail membrane in flight, allowing them to steer with exceptional precision. The megabats (which includes the Old-World fruit bats, such as flying foxes) are well-represented in Spec, being an old group that existed before the K-T boundary. This group includes the largest bats of both RL and Spec. A few true giants have been seen in Spec, and they appear to be slightly larger than the largest RL species, but this remains to be determined. Phyllostomidae, or a group much like it, is present in spec as well. It is from within this New World bat group that one of the most interesting spec lineages has been derived: the Nosferatu. In RL, there are currently only three species of vampire bats, in three genera. The past diversity was greater, with several more species in existence during the Pleistocene, when large hosts (the mammalian megafauna) were prevalent. Some of these extinct RL species also derived larger body-sizes, most likely in response to the availability of especially large hosts. In spec, a megafauna still rules, and thus so do vampires. The Spec Phyllostomidae includes at least 15 species of vampire bats. They are represented by 4 genera. One genus, Nosferatus includes 5 species; all giants by RL standards. The largest, Nosferatus gigas, can obtain a total wingspan of 12 inches, consume 40ml of blood in a sitting. It feeds entirely on large, diurnal dinosaurs. The spec vampires move quickly on the ground, much the same as RL vampires (and in contrast to most bats). They can fling themselves into the air with their arms, hopping about the feet of prey and launching themselves into the air when they are weighed down with a blood meal. The Nosferatus species are all relatively stocky, and can jump and run with amazing power and speed. They are fair flyers, but are not very manueverable in flight. They usually fly low and straight, a cruising height of 1.5 meters is average. They will either land away from a host and walk over to feed, or land on top of an intended host, scampering across it's back delicately to find a good place to take a meal of blood. The nosferatu, which all feed on relatively large (sometimes very large) species, having robust jaws and massive slicing incisors and canines. These teeth are the same ones used by RL vampires to make feeding wounds, but those of the Nosferatu, which must pierce the thick hides of dinosaur prey, are 1.5-2.5 times as large, proportionally. It is as yet unknown how the increased diversity of vampires in spec affects the ecology (including disease transmission) of the Specworld. (Text by Michael Habib) PARASELENODONTIA The assumption that, were it not for the Cretaceous-Paleogene Extinction Event, mammals would be forever destined to be small, annoying furballs cowering in the shadows of a dinosaur's world is proven false to anyone who visits the tundra and boreal forests of the Spec-arctic. Here one finds mysterious hoofed mammals that dwarf anything produced by their Mesozoic ancestors and distantly echo the alternate evolutionary pathway taken by their Arel counterparts. XENOTHERIDIA In RL, virtually all very small herbivore niches (except those in Australia) and then some are occupied by a single giant group of animals, the glires. Rodents and rabbits are ubiquitous across home-Earth's plains, forests, jungles, mountains, deserts, and tundras and take up over a fourth of mammalian diversity between them. In Spec, the glires do indeed, exist, but their evolutionary history is somewhat different. PRIMATES Primates are one of the few lineages of RL mammals that exist on Spec. The familiar appearance of lemurs and lorises may lull a visiting biologist into a false sence to security that would be painfully shattered at the sight of some other Spec primates. ---- - Daniel Bensen, Michael Habib, Matti Aumala , and Brian Choo ---- Works Referenced: Debbie Ciszek and Phil Myers's Tenrecidae ---- ,=CIMOLESTA =Eutheria =| | ,=XENARTHRA `=Placentalia=| | | ,=Tingamarroidae=Tingamaroida nyahnya ( Striped tingamarr ) `=| | ,=Tenrecidae=Feteotenrec bicolor (Stinky tenrec ) | ,=Afrotheria=| | | | ,=Pseudohyrax timidus (Marso ) | | `=Megafrotheridae=| | | `=Setech occultus (Sut ) `=| | ,=Laurasiatheria=Chiroptera=Phyllostomidae=Nosferatus gigas (Nosferatu) `=Boreoeutheria=| | ,?~PARASELENODONTIA | ,=| | | `=XENOTHERIDIA `=Glires=| `=Euarchontoglires=PRIMATES Category:Spec Dinosauria Category:Mammals Category:Animals Category:Alternative evolution Category:Africa Category:South America Category:Asia Category:Europe Category:North America Category:Madagascar Category:Australia Category:Arctic Category:Herbivores Category:Carnivores Category:Omnivores